Incinerator

ABSTRACT

A waste incinerator which includes a housing formed by a heat insulating outer wall, air ducts; a decomposing chamber; a fire room; and a catalytic converter, all disposed in the housing. Waste is introduced into the fire room and incinerated there, and the remains are retrieved from the fire room in such a manner that the incoming materials such as air and waste on one hand the combustion gases and residue on the other hand form a counter flow heat exchange. Various embodiments are disclosed in which the fire wall is or not rotary.

TECHNICAL FIELD

The invention is an improvement in a garbage/wastes/dust/trashincinerator (hereinafter called “machine”. The invented incinerator is amachine comprising a drying chamber (drier), a decomposing chamber(decomposer), a combusting chamber (fire room), a catalytic converter(converter) and a water vapor condenser (condenser). They are integratedsuch that a counter flow heat exchange is effected between the outputand the input, wherein a basic substance is mixed with the waste. Theterm output refers to exhaust gas (exhaust) and the ashes (ash). Theterm input refers to combustion air (air) and waste. The machine needs avery small amount of auxiliary fuel. The emission of pollutants can bereduced to a very low level. The machine is capable of dealing withvarious types of waste. Most of the constituent elements of the machinemay be incorporated in a rotating body. The temperature of exhaust isclose to the room temperature. A scrubber can be directly connected toor integrated with the machine.

BACKGROUND ART

Waste incineration is indispensable to industry for reducing the weightof waste and eliminating the danger of fire, pathogenic organs, andtoxic organic compounds. In addition to harmful or toxic compounds(pollutants), which exist in waste and remain after combustion, such asarsenic, heavy metals and radioactive substances, pollutants are alsoproduced by incineration even if waste has no pollutants. Pollutantsproduced in incineration are causing problem today. Rotating reactor isadopted and/or lime is added in incineration, however, effective resultscannot be obtained.

Burning waste needs oxygen (O₂). Only ⅕ of the air being O₂, burning onemetric ton dried waste needs fifteen ton (11,000 m³) air. Major thermalsubstances of the incineration are water (H₂O) air and exhaust. Exhausthas usually high temperature such as 600-1500 degrees C. Heat ofvaporization of H₂O (latent heat) and heat which is used for heating theexhaust (sensible heat) are wasted into the atmosphere. The latent heatis a large amount of energy. Therefore the total combustion heat (higherheat value) is distinguished from that omitted the latent heat of (H₂O)(lower heat value). Living organisms use higher heat value, but commonburning uses only lower heat value. While (H₂O) is not only producedduring burning, but is also found in waste, latent heat of H₂O from bothsources is wasted. Therefore, 2-5 times of weight of waste auxiliaryfuel is consumed in raw garbage incineration. Incinerating wasteincluding 80-90% H₂O such as sewerage dregs cake, filter remained tofuscum (like a brewer's grains of tofu making) and wasted tofu bean-curd,even 10 times of weight auxiliary fuel can only produce carbidesincluding raw part. In general in these cases, extraordinary amount ofauxiliary fuel is consumed in waste incineration.

Heat recycle arts are described.

Let air and exhaust have the same heat capacity and flow in sufficientlylong pipes, the exhaust being hot and air being cold at each intake.When the two pipes are contacted along their whole length with theintakes being adjacent and the outlets being adjacent, the exhaust andair at the outlets have the same average temperature. This arrangementis called a parallel flow heat exchange (PF). On the other hand, whenthe pipes are so contacted that each intake is adjacent to the otheroutlet, then the temperature at each outlet becomes the same as thetemperature at the corresponding or adjacent intake. This arrangement iscalled a counter flow heat exchange (CF). CF method has been tried inthe dilute fuel combustion.

When a higher temperature air is used, the lower concentrationflammables can be ignited, and nitrogen oxides (NO_(x)), carbon monoxide(CO), soot, etc. can be reduced, and efficiency of energy transformationrate is improved. In some cases trials were conducted wherein fuelcombustion and H₂O vapor in exhaust was not condensed into liquid.

Waste incineration is much more difficult than proper fuel combustion,because waste includes a large amount of H₂O, many nonvolatiles, solidsor various substances, ash remains or residuals. Burning waste producespollutants easily and has various shapes. Therefore, it has beenconsidered impossible in waste incineration to use high technologies,which are difficult to use even in fuel combustion.

Pollutants can be classified into two groups: inevitable and additional.Inevitable pollutants are pollutants which cannot be avoided and includecarbon dioxide, CO₂ and nitrogen oxides NO_(x). If the main flammablecomponents of waste are generally organic compounds, waste incinerationproduces CO₂ and H₂O. CO₂ is not very harmful, but a person can die ifhe is exposed to it in high concentration. Since CO₂ is a globalgreenhouse effect substance, the reduction of its emission is required.Auxiliary fuel also produces CO₂. The reduction of auxiliary fuel isnecessary for saving natural resources, too. CO₂ produced by auxiliaryfuel should be reduced much more than CO₂ produced by waste itself.Incineration of waste formed of a mixture of plastics is, however, is aproblem because it produces pollutants such as dioxins. Electricgeneration exploiting the heat from waste incineration is recommended,however, saving auxiliary fuel is more effective for present technology.

NO_(x) is produced only when the air is heated and its formationenthalpy is positive so that it is decomposed by catalysts. A catalyticconverter of a car utilizes this effect. NO_(x) is hardly produced inincomplete combustion and is reduced when complete combustion gas(oxidizing flame) is mixed with incomplete combustion gas (reducingflame).

Additional pollutants are classified further into nonflammable andflammable pollutants. Nonflammable pollutants include halogen, hydrogenhalides, NO_(x), sulfur oxides (SO_(x)), phosphorus oxide (PO_(x)) andfly ash. Flammable pollutants include organic compounds, carbon, CO,ammonia (NH₃), hydrogen cyanide (HCN), hydrogen sulfide (H₂S) andsulfur. Organic compounds include organic halogen compounds, amines,nitrites, mercaptans, hydrocarbons, alcohol, aldehydes, organic acid andsoot. During a complete combustion flammable pollutants changes intoinevitable pollutants and/or nonflammable pollutants. However, flammablepollutants such as organic halogen compounds cannot be easily combustedcompletely. The pharmacopoeia of many countries and internationalorganizations (USA, Japan, UK, France, European Pharmacopoeia,International Pharmacopoeia, etc.) mentions the “oxygen flask combustionmethod” to measure the quantity of and/or identify halogen (Br, Cl, F,I) or sulfur (S) included in organic compounds. The title of thementioned pharmacopoeia of USA is “Oxygen Flask Combustion”. This methodcomprises the following steps. The organic substance is set in a filterpaper in a platinum (Pt) basket, it is burned in pure O₂ atmosphere andthe quantity of acid gas such as hydrogen chloride (HCl) produced incombustion is measured. Even substance which are very difficult to burn,such as organic halogen compounds can be completely burned under certainfavorable condition, such is pure O₂ and in the presence of a Ptcatalyst.

If additional air is applied in order to achieve complete combustion,then additional auxiliary fuel is also required to provide the sensibleheat. From an economical point of view, an incomplete but nearlycomplete combustion is preferable.

Dioxins are a kind of organic halogen compound, which is an organiccompound combined with chlorine when waste is scorched, and is producedby the burning of organic halogen compounds such as vinyl chloride.Halogen elements and halogen compounds, which vaporize in anincinerator, are called volatile halogens. Organic halogen compoundsdecompose thermally above 180 degrees C. and result in volatle halogenssuch as HCl or Cl₂. Aluminum chloride AlCl₃ (b.p. 183 degrees C.) isalso a volatile halogen. Volatile halogens change organic compounds intoorganic halogen compounds. Production of dioxins can be observed even inthe incineration of waste, which includes no organic halogen compounds,when volatile halogens are produced. Carbon reacts with hydrogen toproduce organic compounds at high temperatures.

Even if organic halogen compounds are decomposed thermally, decomposedmaterials reform into organic halogen compounds again. Volatilesubstances condense in the cooler neighborhood than the boiling pointzone. Organic halogen compounds are volatile at the fire roomtemperature. Organic halogen compounds cannot be easily vaporized inwaste clusters, blocks or wastes buried in ash, and remain or condensetherein, because the raw parts of waste have low temperature.Thereafter, organic halogen compounds may be found in ash when raw partsof waste burn out and the ash cools off for lack of flammables. This isthe mechanism, which results in dioxin being found in the burned outash.

NO_(x) are produced only in the presence of air. More NO_(x) is producedduring burning of waste which includes nitrogen element (N). The waste,which produces acid gas in complete combustion, includes specificelements (N, F, Cl, Br, I, S, P, etc.), which are called acid pollutantelements. Waste including N produces NO_(x) in complete combustion andproduces a flammable pollutant during incomplete combustion which may bereferred to as an acid pollutant such as amine, ammonia, and hydrogencyanide) in incomplete combustion. Acid pollutant is an acid gas,therefore it can be removed by alkaline aqueous solution in thescrubber. But it is impossible that have the scrubber connected to themachine directly or integrated with the machine because the hightemperature exhaust makes the scrubber solution boil.

Combustion is a chemical reaction and raw materials react to producereaction products (positive reaction). At the same time, the reactionproducts react to produce raw materials (negative reaction). Bothreactions are accelerated at high temperature. Negative reaction canhardly happen if the reaction products are removed. Removal of thereaction products to restrain the negative reaction is referred to asdisproportionation. While gases react very fast, liquids slower, solidsvery slow. For example, fuel gas burns explosively but charcoal and cokeburn for a long time. If a part of the reaction products become solid(which do not vaporize, melt or decompose) then the negative reactioncan hardly happen as well. This is also a type of disproportionation.While it is difficult to reduce the negative reaction to {fraction(1/10)} by reaction temperature variation, it is easy to make it lessthan 1/1,000 using disproportionation.

We now consider the materials (basic substances) that react with acidpollutant easily to yield harmless solid compounds (salts) which do notvaporize, melt or decompose even at high fire room temperatures. Basicsubstances render acid pollutants harmless. Metals, oxides, hydroxides,carbonates, hydrogen compounds, organic acid salts, alcohlates andorganic metal compounds, which include alkali metals (K, Na, etc.) oralkaline earth metals (Ca, Mg, etc.), are examples of basic substances.The disproportionation of acid pollutants using basic substances iscalled neutralizing fixation. The total valence number of a base elementper acid pollutant element in the reaction is called a stoichiometricratio. The valence of alkali metals is one and the valence of thealkaline earth metals is two. The stoichiometric ratios of N, halogen, Sand P are one, one, two and three, respectively. The stoichiometricratio of 1 for N is only practical under 300 degrees C., because itssalts decompose above that temperature. Halogen salts such as KCl andCaCl₂ melt under the combustion temperature so that the stoichiometricratio of halogens is practically 1 only under that temperature. Howeverhalogen oxides make their melting points higher, the stoichiometricratio of halogens can practically be ‘two’.

DISCLOSURE OF INVENTION

The following guidelines are used for minimizing the pollutant emission(referred to herein as depollution).

(1).—Auxiliary fuel is used only to heat up the machine initially and tomaintain the flame (Micro-fuel).

(2).—Heat energy for combustion and depollution must be obtained fromthe recycling of the latent heat and the sensible heat.

(3).—Waste must be incinerated utilizing disproportionation under thegood condition like the oxygen flask combustion method of Pharmacopoeia.

(4).—Wasted heat must be reused/recycled as far as possible.

(5).—Inevitable pollutants must be reduced.

If micro-fuel condition is achieved by guideline (1), CO₂ emission isminimized. By guide line (2) waste is dried, a sufficient amount of airis heated for complete combustion, the temperature of the inlet ofconverter is maintained and exhaust temperature is maintained close toroom temperature. Combination of guidelines (1) and (2) achieveguideline (3). Since wastes are combusted with a sufficient amount ofhigh temperature air, flammable pollutants are not produced andguideline (3) is achieved. The scrubber can be directly connectedbecause of room temperature exhaust. Therefore acid pollutants areremoved.

Along with these guidelines, the heat exchange is described first.

The components of the input (i.e., air and waste including basicsubstances) and the output (i.e., the exhaust and ash including remainedbasic substances) include the same elements and have the same totalmass. If the elements and mass are the same, then the heat capacity ofthe smaller molecules becomes larger. Therefore, the output has a higherheat capacity than the input. Thus using CF, air temperature can becomeclose to the fire room wall temperature. Namely

The output heat is sufficient for the air to be heated to the hightemperature of fire room wall.

Waste can be made dry only by the heat of the output.

Therefore micro-fuel can be achieved, when the temperature of the fireroom wall is high. The difference of the heat capacities between inputand the output can be ignored, when the amount of air is more than twotimes that of stoichiometry (more than 10% O₂ in exhaust) or thefraction of H₂O or the ash component is high. In fact, exhausttemperature is calculated as 90 degrees C. in the case of plastic waste,the fire room wall temperature as 1000 degrees C., the room temperatureas 25 degrees C. and the remaining O₂ is 10%. In this case, the scrubbersolution does not boil even if the scrubber is directly connected.Namely;

Exhaust temperature can be close to the room temperature.

The scrubber can be directly connected or integrated.

The fire room wall temperature becomes high enough using CF method underthe following condition. The combustion temperature becomes higher whenthe amount of air is a little less than the stoichiometric amount. O₂ isinsufficient for complete combustion under this condition. When thecombustion temperature is high, then waste is decomposed effectively andthe combustion goes well. Air must be shared so that air is nearly thestoichiometric in the center of fire room. Since heat is conducted fromthe fire room to the atmosphere by heat insulation, the heat insulationacts as a heat conductor. The coefficient of heat transfer is thethermal conductivity divided by the thickness of heat conductor (heattransfer length). The conductive product is the conduction sectionmultiplied by coefficient of heat transfer. The product indicates theability of the heat exchange. A machine must be designed so thatconductive product is large enough in the heat exchanger, makingconduction section large and the heat conductor thin. All parts in amachine (waste transporter, ember transporter, ash transporter, ceramicsfixing plates, scrubber wall, connecting points or area of parts and theothers) must be considered as heat-conducting elements such as heatconducting fins, heat radiating fins, heat accepting fins or heatreflecting fins. The conduction section should be as large as possible,paying an attention not to enlarge the gas flow resistance. For example,air pipes in exhaust enlarge conductive section. In the low temperaturezone including condenser, the diameters must be large and many or largeheat fins are arranged for the exchange of big heat of condensation. Butthe thermal conductivity of liquid H₂O, which is about twenty times ofair, moderates the condition. The large surface of the high temperaturezone (hot zone) cools fire room, since it enlarges conductive product.The fire room must be as small as possible and so must be hot zonearound the same. Air ducts should surround all hot zone components, andthe heat radiation must be reflected by heat reflectors at all windowsexcept the intake of converter, which must be hot. The whole body mustbe wrapped with thick heat insulators.

The heat energy in the fire room (higher heat value added by therecycled heat) equals to the emission heat (emitted directly from theouter wall of fire room to the atmosphere) plus the transferred heat(heat of exhaust and ash). The transferred heat equals the recycled heat(recovered as the heat of air and waste to fire room) plus theunrecycled heat (not recovered to fire room). The unrecycled heatincludes the heat, which is harvested by the heat utilizing apparatus(utilizer). Since both heat capacities of incoming and outgoing arealmost equal, the unrecycled heat becomes almost the same as heatharvested by utilizer. The harvested heat must not be so large as toreduce the combustion temperature. Therefore, the emission heat equalshigher heat value minus the unrecycled heat. The fire room walltemperature is the emission heat divided by conductive product plusexternal wall temperature. The combustion temperature becomes 100-500degrees C. higher than that of fire room wall (inside). When higher heatvalue is larger than the unrecycled heat, the reduction of conductiveproduct can make the fire room wall temperature high. This higher heatvalue is larger than the lower heat value of dried waste. Namely;

Even wet waste can burn almost the same temperature as dry one.

A machine has rotating parts and surface areas that can be at 50-80degrees C. Protective walls which have interiors acting as external airducts, cover these dangerous areas. Sucking external air by air inletfans, leaked gas and heat can be returned to the machine.

The accumulation of such small devices follows a big effect. Thereby theheat exchange rate and the fire room wall temperature can be high.

There is waste that is difficult to ignite even if dried, because itshigher heat value is almost zero, or includes too much H₂O to get thenecessary conductive product value. Therefore, a little more auxiliaryfuel is needed in these cases.

Most of the purpose of incineration of waste is the reduction of weightof the waste. This indicates that the amount of ash or the heat capacityof ash can be ignored. Namely, in the most case of waste, ash is ignoredin heat exchange calculation. Once depollution and micro-fuel areachieved, a machine is recommended to be designed so that manufacturingcost is low and the handling convenience have priority over a smallvariation of the rate of the wasted heat utilization.

Base and neutralizing fixation are described, next.

The most suitable basic substances are oxides, hydroxides, andcarbonates. Alkaline earth metals are suitable for the invention becausethe porosity ceramics within the converter is less damaged by them.Calcium compounds calcium compounds i.e. quick lime (calcium oxide CaO),slaked lime (calcium hydroxide Ca(OH)₂ and limestone powder (calciumcarbonate CaCO₃) are the most economical. In fire room, Ca(OH)₂ producesH₂O and CaCO₃ produces CO₂. Both CaO and Ca(OH)₂ are produced bakingCaCO₃ and emitting CO₂. CaCO₃ has advantage in CO₂ produced by bakingfuel from the global point of view. CaO has a problem of safety. CaO andCaCO₃ are difficult to obtain in as a fine powder. Ca(OH)₃ hasadvantageous from these points.

Each acid pollutant element shows certain characteristics duringneutralizing fixation. Above 180 degrees C., organic halogen compoundsdecompose thermally and give off volatile halogen, which react with abasic substance. Since the halogen salts melt at high temperature,neutralizing fixation is effective under 700 degrees C. Therefore, thestages of the fixation are before fire room and in exhaust (in theconverter, condenser and the scrubber). In the fire room, the organicmatter bums and is reduced. If there is only little organic matter, thenvolatile chlorine can hardly react with it to produce organic chloridesin the reverse or negative reaction.

Concerning S, since decomposed matters such as sulfur or hydrogensulfide do react not easily with basic substances, S must be changedinto SO_(x), which is produced when they are burned, for neutralizingfixation. The fixation occurs in the fire room and in the exhaust.

The neutralizing fixation of N is only effective in the exhaust under300 degrees C. NO_(x) is an oxidizing agent and helps to eliminateflammables. After maintaining NO_(x) in moderate concentration using theoxidizing flame and reducing flame mixture, and the catalytic effect inthe fire room, NO_(x) is removed in the converter, condenser and thescrubber.

The catalyst is described next.

Exhaust from fire room is passed through the secondary combustingchamber namely the converter, where ceramics, which include oxides oroxoacid salts or double oxides of silicon and/or aluminum and/orzirconium as main components, are disposed. These ceramics act catalystlike Pt over 600 degrees C. The catalyst adsorbs gas molecules such asO₂, SO_(x), Cl₂ on its surface and compress them to high pressure.Therefore even matter, which is difficult to burn or which is too diluteto burn in the air, can burn well. The more surface the ceramics have,the more effective they are. Therefore porous ceramics, which have largesurface, must be used. This includes ceramics with both the microscopicone and the macroscopic porous surfaces. The later includes fibrous,sintering, thin plates, foamed/ballooned, mall pipes and other similarcomplex compounds. Ceramics are shaped to form air passages to reducethe flow resistance and may be in the form of lumps, blocks, honeycomb,plates, cloth, and like cotton wool. Ceramics can be more effective whenthe catalysts are charged with Pt, Pd, ZnO₂, chromium oxides, ironoxides, nickel oxides, cobalt oxides, manganese oxides and so on, whichare developed by the chemical engineering arts or uses as catalysts inthe catalytic converter of a car. Minerals which may be mixed withceramics may also improve the effectiveness of the catalysts. Pt andlike have effects of acceleration of burning, oxidation, anddecomposition even at room temperature when they are charged in the lowtemperature zone (less than 500 degrees C.). However, ceramics have thesame effect with Pt and like when the intake of converter is kept over600 degrees C. and preferably around 700 degrees C. When air heats up toover 300 degrees C., the combustion is accelerated. recognizably. Evenwhen rubber is burned, fumes disappeared. ZrO₂ and like have specially agood effect to decompose NO_(x) and make it to thermal equilibriumconcentration. Therefore, materials, which include ZrO₂, must be usednot only in converter but also on fire room wall, as castable-cement,fire cement, etc. The converter makes flammables burn, NO_(x)decomposes, acid pollutant changes into higher oxides and particles staythere by filtration effect. Soot particles burn in the O₂ at existinghigh temperature area. Neutralizing fixation happens in converter whenbase particles are assembled therein. The more oxygen atoms molecular ofacid pollutant has (the higher oxide acid pollutant is), the more easilyit is dissolved in H₂O and the stronger as acid it becomes. Therefore,it improves the efficiency of the scrubber that acid pollutant ischanged into higher oxide. Namely, converter increases depollutioneffect of condenser and the scrubber. The combination of flammablesburning out and neutralizing fixation has a large effect in removingorganic halogen compounds, too. Before entering converter, organichalogen compounds almost disappeared by neutralizing fixation and goodcombustion condition in fire room. When a small amount of organichalogen compounds decomposes thermally to give halogens and organiccompounds in converter, halogens are neutralized and fixed and organiccompounds are burned out. Both reaction products disappeared and thereverse reaction cannot occur. Therefore the converter is an extremelyeffective apparatus for the removal of organic halogen compounds. NO_(x)reaches the equilibrium concentration depending on the temperature bythe catalysts. The lower the temperature is, the lower the equilibriumconcentration becomes and the longer time is needed to achieve theequilibrium. NO_(x) concentration becomes low in shorter time, when itsentrance temperature and its exit temperature are made high and low,respectively.

The combination of converter and the sufficient amount of the hightemperature air, which includes NO_(x) and is obtained by heat recycle,can be substituted for pure O₂ and the Pt basket described inPharmacopoeia.

The water vapor condensation is described.

Water vapor, which originates from the moisture of waste, lowers O₂concentration and prevents complete combustion. If the water vapor isdischarged by the exhaust fan, the same volume of air cannot beabsorbed. The water vapor condenser acts a pump, the capacity of whichis the decreasing volume from gas to liquid. The absolute quantity of O₂for the combustion can remain constant independently of the moisture ofthe waste, when water vapor is condensed or removed before discharge.The condenser is used not only to save the heat for drying wet waste todryer, but also to help the combustion concerning O₂. O₂ changes intothe same mole of CO₂ in combustion. Both the input air and exhaust havealmost the room temperature. Therefore both air and exhaust have almostthe same volume. This condition makes the design and establishment ofair fans and exhaust fan easy. Since the thermal conductivity of H₂O is20 times that of the air, the ability of heat exchange using H₂O isincreased. When the H₂O vapor is condensed, H₂O catches harmful acidgases and acid pollutants and removes them, similar to the way that rainremoves smog. However the condensed H₂O is a strong acid, with a pH ofabout 2, which corrodes the materials of the machine. In order to avoidthe corrosion, it must be neutralized by the alkaline scrubber solution.The scrubber solution, which is warmed by exhaust, warms waste and itsdrying is accelerated.

The integration of the scrubber to the machine can increase theefficiency even more. But it is better that the machine, especially fordry waste, have an independent scrubber because of the small effect ofthe integration.

The ability of absorption of acid gases in the condenser is increasedbecause the condensed water is neutralized by the alkaline scrubbersolution preferably to remove acid gases/pollutants in converter, thecondenser and the scrubber are located directly after converter. Thusthe ability of converter is increased so that organic halogen compoundsare controlled effectively. Since condenser and the scrubber can act aswet type air cleaners, dust particles in exhaust are removed here. Basicparticles such as fly ash are also caught here and utilized again in thescrubber.

Ash in the machine is now described.

When ash increases the flow resistance, an air intake fan especially forash (ash air fan) is set, so that the shortage of hot air for ash isprevented. While embers are burning out, their flammable materialcontent decreases and embers become more difficult to burn. Fresh hotair is made flow in the reverse direction of the motion of ash. Then,while embers are burning out, they can be exposed to fresher hot air.Thus embers can burn completely. At the same time the volatilepollutants are vaporized and blown back to the fire room and they areprevented to remain in ash. When ash stays long time in high temperature(more than 650 degrees C.), it becomes dense. The post treatment ofdense ash is easy. If waste is in lumps/clusters or in the form ofdumplings and it is exposed to insufficient air or is not maintained athigh temperature until it burns out then volatile pollution such asdioxin remains in ash. In order to prevent forming of waste lumps, wasteis cut and crushed to small size before the incineration. Cascade stepsare made in fire room to maintain the embers in air long time and toexpose them to air. A rotary kiln can be used in order to drop, turnover or tumble upside down waste/embers repeatedly, except the case ofthe waste which include no halogen or leaves little ash. Namely, wasteand embers are kept hot, exposed to air, divested of cool place andexposed to fresh hot air until burn out, so that volatile matter doesnot remain in the ash.

The flows of air and waste are described.

The air inside the protective wall is inhaled by air inlet fans (airfans) and moves from the cool area to the hot area, namely outside ofthe scrubber, through the condenser and the converter, to the fire room.Air becomes almost as hot as the fire room wall temperature. The routefollowed by air is called the intake air duct. Exhaust is cooled in theconverter, in the condenser (where H₂O is condensed), out of utilizerand in the scrubber. The O₂ concentration is measured, and discharged tothe atmosphere by exhaust fan. The route where exhaust flows is calledthe exhaust duct. The rate of introducing of waste and air anddischarging of exhaust are regulated so that the O₂ concentration in theexhaust is kept above 10%. However O₂ concentration can be regulated tobe lower than 10% in the cases where the H₂O content of waste is veryhigh or when the production of pollutants is low. O₂ cannot be measuredif the waste characteristics remain constant. In this situation, themachine may be set or designed using calculated or empirical O₂ values.The exhaust fan must have larger capacity than air fans. This capacitydifference combined with the pumping effect of condenser results thefollowing effect. The valance air is inhaled from the waste storage tankand caries bad smell into the waste duct. This air helps waste dry andwater vapor and volatile matter to be transported and becomes a part ofcombustion air in decomposer. Because exhaust side (scrubber side) haslower pressure than the side of atmosphere, air and waste, the leakageof exhaust and the condenser/scrubber solution through seal/gaskets oropen windows/leaks are prevented. Dangerous area has lower pressure thanthe safety area. When a rotary kiln is used, seal means becomenecessary. But, the above-mentioned negative pressure structure makesthe seal means easier. For example, short pipes or doughnuts are formedby 2-5 sheets of ceramic cloth such as glass or kaolin. The one side ofthem is attached to fixed body and in another side the rotating body.And they are let through and pressed by the loosely tensioned ceramic orglass thread/yarn/string. The pipes or the doughnuts are sewn with thethread to prevent coming loose and coated by grease to prevent theleakage of gas or water. Such simple sealing can work.

After the waste is cut to small, crushed and mixed with base, it isquantitatively fed into dryer. The amount of the basic substance must bemore than the stoichiometric ratio (usually 1.3-2 times of that). NaOHor KOH is usually used as basic substance in the scrubber because theyboth are well dissolved in H₂O. Ash, which includes no pollutant, can beused as basic substance for the scrubber, as well. Some waste is in theform of sticky substance which melts before burning, produces bad smellswhen mixed with a basic substance. In addition, in some types ofmachines in which it is difficult to use ash as a basic substance. Suchmachines need base introducers. The introducers introduce all or part ofbasic substance in form of a powder into the machine. Such a powderprevents waste from sticking. The powder becomes fly ash easily.

Waste is supplied into the fire room through the dryer and thedecomposer. The route, where waste moves through, is called the wasteduct.

Waste is dried in the dryer by the heat from the scrubber solution,condensed H₂O and the exhaust. However dry waste needs not to be dried(the dryer is not necessary). The waste obtains heat in the decomposer,decomposes thermally and bums partially. If waste includes componentswhich have low volatile temperature and low flash point, flames can beformed and spread out not only in the decomposer but also in the dryerand explosive combustion can be caused repeatedly. In order to avoidthis, the waste duct must have narrowed necks in the dryer, in thedecomposer and/or the boundaries thereof.

Organic halogen compounds are neutralized and fixed in solid in thedecomposer as well.

In fire room, a pilot light is initially turned on and remains on. Thepilot lamp can be extinguished when the temperature is higher thanauto-ignition point (air is hotter than 650 degrees C.) and thecombustion heat of waste can maintain the fire room temperature. Thepilot light is selected so that it has an igniter and it burns using airin fire room. Therefore air must be supplied around the pilot light tokeep it on. Since the lamp needs only small amount of fuel, O₂concentration is not lowered considerably by the pilot light and thewaste is not blown away toward the exit, as it is the case with strongburner which is used in conventional incinerators.

ZrO₂, which is included in the refractory material of the fire roomwall, makes the NO_(x) concentration close to the heat equilibriumconcentration at the fire room wall temperature. Part of reducing flameis mixed in fire room with the oxidizing flame in order to restrain theconcentration of NO_(x). SO_(x) is neutralized and fixed in the solidsin the fire room, so that basic substances must be incorporated in thefly ash there, as well. In the fire room, organic compounds are reducedso that organic halogen compounds are prevented from the reproduction.However, almost all halogen compounds become gas or liquid in the fireroom. Therefore they are scarcely fixed in solid. Plural air suppliersin the chamber make the temperature of the center high. Enough O₂ mustbe supplied in order to combust the waste completely except at thehottest part in fire room.

The temperature at the entrance side of converter must be kept high andthe temperature of the exit side low. Since porous ceramics are goodheat insulators, this temperature gradient is easily attained. Theeffect is advantageous to the reduction of the conductive product of thefire room. It must be kept in mind that an incomplete combustion in fireroom increases the combustion in the converter, so that converterbecomes hotter than the fire room. In such case the porosity of ceramicsis damaged and the cooling of the exit side becomes incomplete. Beforethe exhaust flows into converter, the air must be mixed with the exhaustcompletely in the fire room, which must has sufficient burning space andthe air velocity must be depressed (under 10 m/s converted to the roomtemperature). Not only artificial ceramics but also natural materialssuch as pumice stone and lava can be applied to the catalyst, the formerbeing easier to be applied. While natural materials include somepollutants such as sulfur, they must be strongly fixed by the refractorycement so that they are not braised. The flow resistance through theceramics should be minimized. Therefore recommended shapes for converterare plates (including wool plates) or cloth that are/is piled up orrolled with spacers, formed honeycomb like coaxial circles (FIG. 8, 9),nest structure (FIG. 10), radial (FIG. 11), sieves (FIG. 12), star like(FIG. 13), etc. The shapes of the ceramics in converter are selected byalso considering dropping or removing of fly ash from the ceramics,homogeneously exhaust blowing to heat exchanging face and the collisionof particles and usually selected among or combination of FIGS. 10, 11,12. If the simplest shape is preferred, then blocks are selected. Thebasic substance has also a catalytic effect and is introduced into theconverter as fly ash. In the converter, soot particles are trapped andthey stay and eventually burned away. NO_(x) is decomposed, acidpollutants are changed into higher oxides and neutralized and fixed inthe solid basic material. Fly ash and even dilute organic compounds areburned away. The ceramic materials in the converter makes a secondarycombusting burner unnecessary and this leads also to fuel saving. Inconventional incinerators, a very big burner or big burners are used asa primary or as a secondary combusting burner.

In the condenser, H₂O vapor in exhaust is cooled by air and waste, andcondensed into liquid there. When air temperature is high enough (abouthigher than 700 degrees C.), steam, hot water, warm water, hot air orwarm air can be obtained from the utilizer by cooling exhaust. For theconventional art, more air than stoichiometric requirement for completecombustion is provided, and the waste, which includes the much H₂O ormuch ash component, are no more than the auxiliary fuel consumers. Butfor the invention, these components are good coolants having large heatcapacity.

When the combustion heat of waste is large enough, the utilizer can beplaced in wide range from the low temperature zone to the hightemperature zone (around the exit of converter) and large amount of heatcan be obtained. When only little amount of heat is obtainable, utilizeris placed about the outlet of the scrubber and warm water is obtained.When the air is not hot enough, excess heat utilization causes airtemperature decrease, the lack of air heating and the decrease ofpollution controllability of converter.

In the scrubber, the exhaust is cleaned by the solution. Various typesof scrubbers can be used, such as a spray packed tower, a net platestower, a helical flow tower and a biflex tower. A scrubber which ischaracterized with by a large flow resistance I undesirable. A part ofthe scrubber solution is introduced into the condenser so thatefficiency of the heat recovery increases and the life span of thesolution is lengthened. Since the condensed H₂O is hotter than thescrubber solution, it can dry waste and heat up the air. The restraintof mixing with the scrubber solution helps the condensed H₂O to remainhot. When wet waste is burned and all the solution are fed into thecondenser, then the condensed H₂O dilutes the solution and a lot of weakalkaline water must be drained. The solution should be let intocondenser so that the condensed water is almost neutral. Then thedrained water can effectively warm up the water of the utilizer. Thescrubber circulating solution or combustion air can be warmedpreliminary by the heat of condensed H O.

As described above, air is let into fire room after being heated outsideof the scrubber, in the condenser and the fire room. Waste is movedinside of exhaust duct. Ash is moved in part of the air ducts in thereverse direction of airflow and is taken out. Micro-fuel anddepollution are achieved in this structure when heat is sufficientlyexchanged between the input and the output, the neutralizing fixation isaffected and the converter is operational.

0.5 kg/hr auxiliary fuel was supplied to the pilot light of a testmachine. Filtered remains of tofu scum, wasted tofu bean-curd andsewerage dregs cake was used as waste, each of which include 80-90% H₂Oand could burn at a rate of 100 kg/hr. The air temperature was 640degrees C. before the waste introduction. It decreased to 635 degrees C.just after the introduction and then increased to 650 degrees C. andremained constant at that level. The temperatures of both exhaust andthe scrubber solution were not higher than 5 degrees C. over room orambient temperature. Neither smoke nor smell could be detected. AKitagawa detector detected neither NO_(x) nor SO_(x). When anextinguishing fire hose composed of urethane and vulcanized rubber wasincinerated, air temperature became higher than 700 degrees C. andexhaust was cooled by the utilizer. Neither smoke nor smell could berecognized. And neither NO_(x) nor SO_(x) were detected.

The invention can also be applied for the manufacturing processes whichproduced is ash, such the production as cement, and quick lime. Evenwhen the waste does not have enough heat for combustion, saving fuel andpreventing of pollutants are accomplished by using a small amount ofauxiliary fuel or mixing coal powder or tire chips in waste. Since thetemperature of exhaust is almost the room temperature, the machine caneasily be made into a closed system.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1-5 are vertical sections including rotating axis of desirableexamples of the invention using a rotary kiln.

FIGS. 1-4 show arrangements wherein an air duct, a dryer, a decomposer,a fire room, a converter and a condenser are provided on a rotatingbody.

FIG. 5 shows an arrangement in which only part of air ducts and a fireroom are made in a rotating body.

FIGS. 1-3 and 5 show arrangements wherein the rotating body lieshorizontally.

FIG. 4 shows an arrangement with an inclined rotating body.

FIGS. 2 and 5 show arrangements with a constant diameter.

FIG. 1 shows an arrangement in which the diameter varies stepwise.

FIGS. 3 and 4 show arrangements wherein the diameter varies gradually.

FIGS. 6 and 7 show the vertical section of desirable examples of theinvention which do not use rotating body.

FIG. 6 shows the machine for the waste that results in an output whichdoes not contain large amounts of combusted residue.

FIG. 7 shows the machine for the waste that results in a large amount ofcombusted residual such as tire or FPR.

FIGS. 8-13 show the front views and right side sections of theconverter, the ceramics of which are plates or cloth.

Explanation of symbols  1 waste storage tank  2 flue pipe  3 crusher  4stirrer/collecting arm  5 waste introducer  6a tire holding plate  6btire intake/residual outlet  6c tire stopper  6d residual storage  7base substance storage tank  8 base substance introducer  9 dryer 10waste transporter 11 heat reflector 12 decomposer 13 waste transporter14 heat reflector 15 waste push-outer 16 air fan 17 ash air fan 18 heattransferring fin 19 air duct 20 ash transporter 21 secondary air port 22primary air port 23 ash air port 24 base substance scatter 25 fire room26 pilot light with igniter 27 ember transporter 28 cascade steps/embersdropper 29 waste scatter 30 smoke homogenizer 31 heat reflector 32 smokebypass 33 main temperature sensor 34 temp. sensor 34a primary airtemperature sensor 34b steam pipe temperature sensor 35 catalyticconverter 36 ceramics/catalyst 37 ash out-letting flight 38 condenser 39condenser fin 40 heat utilizing pipe 41 heat transferring pipe 42alkaline scrubber 43 O₂ 44 exhaust fan 45 ash out-letter 46 ash storage47 scrubber solution drain 47a circulating solution outlet 47b condensedwater drain 48 heat utilizing means (utilizer) 49 drain tank 50 scrubbersolution tank 51 pump 52 protective wall 53 demister 54 outer wall (heatinsulated) 55 middle wall 56 inner wall 57 rotator 58 rotating tire 59pilot light support 60 gasket 61 external air duct 62 waste lifter 63neutralizer valve 64 neutralizer inlet 65 utilizer inlet M motor F fan Ppump

BEST MODE OF CARRYING OUT THE INVENTION

The invention is capable of dealing with various types of waste and tobe adopted to various types of incinerators devised for various forms orstates of waste as a fire room. The mode of carrying out the inventionadopting a rotary kiln is more effective to reduce the emission ofpollutants. The mode of carrying out the invention without a rotary kilnis more easily matched with heat utilizing or the state of waste, needsless manufacturing cost per capacity and can be large equipment.

The embodiments of the invention are described using FIGS. 1-7.

A machine of a first embodiment shown in FIG. 1 has air ducts (19), adryer (9), a decomposer (12), a fire room (25), a converter (35), and acondenser (38). These elements are installed in a horizontally laidrotary kiln, the inner diameter of which is varied stepwise and withwhich a scrubber (42) is integrated. The machine itself acts the counterflow heat exchanger between incoming and outgoing. Waste is introducedquantitatively from waste storage tank (1) through a crusher (3) into adryer by a waste introducer (5) that has a screw blade. Malodorous gasesin waste tank are vented to the dryer through a flue pipe (2). A basesubstance is quantitatively introduced from base tank (7) into the dryerby the base introducer (8). Heat reflectors (11,14) in waste ductprevent backfire. A long pipe is inserted from waste introducing sidealong the axis of the kiln, and includes a pilot light (26) with anigniter and a temperature main sensor (thermocouple). Waste transporter(10,13) and ember transporter (27) are made of dropping flights, whichhave oblique plates. Ash transporter (20) is made of intermittentmultiple spiral plates. A waste lifter (62) is made of a long droppingplate, which has an oblique plate and transports waste in thediameter-varying zone. The inner wall (56) and the middle wall (55) havespiral plates (37,39), which bail out the condensed water. Only part ofthe scrubber solution is introduced into condenser (38) and the scrubbercirculating solution outlet (47 a) is separated from the condensed waterdrain (47 b) where the water in utilizer is pre-warmed. The warmed waterflows outside of the large diameter part of condenser and is heated(65,40). Since the large area of condensation increases the efficiencyof utilizer, this embodiment suited for waste that is easily cut smalland has wide range of heat of combustion.

A machine of the embodiment shown in FIG. 2 has air ducts (19), a dryer(9), a decomposer (12), a fire room (25), a converter (35), and acondenser (38). These elements are installed in a horizontally laidrotary kiln and the diameter of which is constant. The machine itselfacts the counter flow heat exchanger between the input and the output. Ascrubber (42) is independent and neutralizing solution is regulated bythe valve (63) and supplied to condenser. Waste is quantitativelyintroduced from the waste storage tank (1) to dryer by a wasteintroducer (5). Malodorous gases in the waste tank are vented to thedryer through a flue pipe (2). Heat reflectors (11) in waste ductprevent backfire. The pilot light supporter (59), which includes a pilotfire with an igniter (26) and a main temperature sensor (thermocouple)(33), is inserted along the rotating axis and allowed the axial swingbut inhibited the rotation by the universal joint in order to connectwith the fixed base. Waste transporter (10,13) and ember transporter(27) are made of dropping flights, which have oblique plates. Ashtransporter (20) is made of intermitted multiple spiral plates. Each ofthe inner wall (56) and the middle wall (55) has a spiral (37,39), whichbails out the condensed water. The rotating body is the simplest in FIG.1-4. The embodiment is best suited for dry waste.

A machine of the embodiment shown in FIG. 3 has air ducts (19), a dryer(9), a decomposer (12), a fire room (25), a converter (35), and acondenser (38). These elements are installed in a horizontally laidrotary kiln, the diameter of which is varied gradually and with which ascrubber (42) is integrated. The machine itself acts the counter flowheat exchanger between the input and the output. Waste is quantitativelyintroduced from waste storage tank (1) through a crusher (3) into adryer by a waste introducer (5), which has a screw blade. Malodorousgases in waste tank are vented to the dryer via a flue pipe (2). A basesubstance is quantitatively introduced from base tank (7) to dryer bybase introducer (8). Heat reflectors (11,14) in waste duct preventbackfire. The pilot light supporter (59), which includes a pilot lightwith an igniter (26) and a main temperature sensor (thermocouple) (33),is fixed to the machine base. Waste transporter (13) and emberstransporter (27) are made of dropping flights that have oblique plates.Ash transporter (20), waste transporter (10,62) and condenser fins (39)are made of single continual spiral. Long dropping plates (37), whichhave oblique plates, transport fly ash from converter to the condenser.Condensed water is bailed out by the diameter variation and the spiralplate (39). Since the condensation area is big, the embodiment is suitedfor slightly wet waste.

A machine of the embodiment shown in FIG. 4 has air ducts (19), a dryer(9), a decomposer (12), a fire room (25), a converter (35), and acondenser (38). These elements are installed in an inclined rotary kiln,the diameter of which is varied gradually and with which a scrubber (42)is integrated. The machine itself acts the counter flow heat exchangerbetween the input and output. Waste is quantitatively introduced intodryer from waste storage tank (1) via a crusher (3) by a wasteintroducer (5), which has a screw blade. Malodorous gases in the wastetank are vented to the dryer via a flue pipe (2). A basis substance isquantitatively introduced from base tank (7) to dryer by base introducer(8). Heat reflectors (11,14) in waste duct prevent backfire. A pilotlight supporter (59), which includes a pilot light with an igniter (26)and a main temperature sensor (thermocouple) (33), is fixed to themachine base. Ceramic blocks (35) are fixed by the refractory cementincluding ZnO₂ powder. Waste transporter (10,13) and ember transporter(27) are made of dropping plates. Ash transporter (20), wastetransporter (62) and condenser fins (39) are made of single continualspiral. Long dropping plates (37), which have oblique plates, transportfly ash from converter to the condenser. Condensed water is bailed outby the diameter variation and the spiral plate (39). Because hotcondensed water makes a pool, waste can be easily dried. Since thecondensation area is big, the mode is suited for wet waste.

A machine of the mode shown in FIG. 5 has a fire room (25) and part ofair ducts (19). These elements are installed in a horizontally laidrotary kiln, and the rest of air ducts (19), a dryer combined wastestorage tank (1,9), a decomposer (12), a converter (35), a condenser(38), and a scrubber (42) are fixed to the machine base. All of them areso integrated that the machine itself acts the counter flow heatexchanger between the input and the output. After mixed with the basicsubstance and stirred by an arm (4) in dryer (1,9), waste isquantitatively introduced to fire room via decomposer by wastetransporter (5). The transporter has a spiral (10) and a hollow poredshaft (2). The shaft vents water vapor and volatile matter such as gasesin the tank or decomposer to the fire room. The hollow shaft preventsbackfire. A pilot light supporter (59), which includes a pilot lightwith an igniter (26) and a main temperature sensor (thermocouple) (33),is fixed to the machine base. Ember transporter (27) is made of droppingflights that have oblique plates. Ash transporter (20) is made ofintermittent multiple spiral plates. Fly ash considered the form of theceramics is made radial in the lower part and nest structure in theupper part. The embodiment is suited for waste which has rather largecombustion heat or which is rather hard to cut fine, because heatrecovery becomes rather insufficiently.

A machine of the embodiment shown in FIG. 6 has air ducts (19), a dryerand waste storage tank (1,9), a decomposer (12), a fire room (25), aconverter (35), a heat utilizer, a condenser (38), and a scrubber (42).These elements are so integrated that a machine itself acts the counterflow heat exchanger between the input and the output. After being mixedwith the basic substance and stirred by an arm (4) in dryer (1,9), thewaste is quantitatively introduced to fire room via decomposer by wastetransporter (5). The transporter has a spiral (10), a stirring arm (4),and a pored hollow shaft (2). The shaft vents water vapor and volatilematter such as gases in the dryer or decomposer to the fire room. Theshaft prevents backfire. The stirring arm is so bent that it gathers thewaste. The machine must have many waste introducers when its size ismade large. Waste is scattered uniformly in fire room by a waste scatter(29). Fly ash considered the form of the ceramics is made radial in thelower part and nest structure in the upper part. Each of primary airport (22), secondary air port (21), and ash air port (23) is made ofpipe array, on the under side of which air nozzles are so lined that aircan be supplied homogeneously. This device increases the area ofcondensation so that the efficiency of heat utilization is improved. Theembodiment is suited for such waste which has medium or large combustionheat, leaves little ash, produces little pollutants and is not easy orrather difficult to cut small.

A machine of the embodiment shown in FIG. 7 is suited for such dry wastewhich has big heat of combustion and remains as large size of residualbut with little ash. Waste such as tire is expensive to cut, because thecutter is very expensive. For this type of waste, both quantitativesupply of waste and takeout of residuals is difficult. Therefore ash,residuals and waste are excluded from the object of heat exchange withair and exhaust. Air ducts, a decomposer (12), a fire room (25), aconverter (35), a condenser (38), and a scrubber (42) are so integratedthat a machine itself acts the counter flow heat exchanger between theair and the exhaust. A tire in-taker combined with a residual outlet (6b) is pulled out to the dashed line and a tire holding plate (6 a) isalso pulled out to the dashed lines. Then tire drops into tire in-takerfrom a tire (waste) storage tank (1). Tire holding plate is returned toits initial position immediately. Then tire in-taker is also returnedand tire is set in the decomposer. The tire is quantitatively decomposedand burns slowly in decomposer as r regulated by fan (17) and thedecomposed/vaporized gas burns in fire room. The tire burns out and theresiduals are left in residual out-letter (6 b). Tire stopper (6 c) ispulled out to the dashed line. Residual out-letter is then pulled to thedashed line. The residuals drop into a residual storage (6 d). All arereturned to the initial position describing as the solid line. The tiremust be introduced into decomposer after the primary air temperature (34a) becomes 600 degrees C. or higher by initial heating. In thedecomposer, the tire is slowly decomposed, vaporized and combusted andash and embers drop onto cascade steps (28) and large size of residualsare left in decomposer. Embers are completely combusted in cascadesteps, where a pilot light exists and hot fresh air is supplied. Theleakage of smoke from a machine is prevented by the difference of thecapacity between air fans (16,17) and an exhaust fan (44) even when tirein-letter is pulled out and the inside of a machine is exposed. Suchgases, as are produced when tire touches the hot in-letter, do not leak,because the air inside the protective wall (52) is inhaled to a machineby air fan (16). A machine that has several sets of tire introducer (6a, 6 b, 6 c and 6 d) can stabilize the temperature in decomposer and hashigh efficiency of handling. Plural number of base suppliers (8)quantitatively supply the basic substance into fire room (25) from basestorage tank (7). The basic substance is scattered homogeneously in fireroom and made fry ash. Each of a primary air port (22), a secondary airport (21) and an ash air port (23) is made of pipes array, on the underthe side of which air nozzles are so lined that air can be suppliedhomogeneously.

INDUSTRIAL APPLICABILITY

The invented machine needs very little amount of auxiliary fuel, emitsonly very low level of pollutants. It can be applied for various typesof waste. It is applicable to such waste as rubber or plastics that havevery large heat of combustion. It is applicable to the waste such assewerage dregs cake that includes much water and is difficult to burn orignite. It is also applicable to such waste as tire and FRP that resultsin large sized residuals. The invention is applicable to cement or quicklime production.

What is claimed is:
 1. A waste incinerator comprising: a heat insulatedbody; a rotating housing formed within said heat insulated body, saidrotating housing including a fire room receiving waste for burning, anair duct conducting combustion air to the fire room, an exhaust ductconducting exhaust from said fire room, said exhaust being produced bythe burning of said waste, said exhaust duct being oriented to conductsaid exhaust in a reverse direction with respect to said combustion air,said exhaust duct and said air duct forming a counter flow heatexchanger; a waste moving member arranged to move said waste to saidcombustion chamber for combustion; a catalytic converter disposed withinsaid heat insulated body and receiving said exhaust from said exhaustduct to remove pollutants from the exhaust; a water vapor condenserdisposed within said heat insulated body and receiving said exhaust fromsaid catalytic converter, said water condenser being adapted to removewater and acids from exhaust; and a scrubber disposed within said heatinsulated body and receiving said exhaust from said water condenser toremove particulate matter, said scrubber using a scrubber solution whichis recirculated to said water vapor condenser to neutralize said acids.2. The waste incinerator of claim 1 further comprising a waste storagetank holding waste before said waste is moved by said waste movingmember to said fire room, another tank holding a basic substance; and anintroducer that introduces said basic substance from said another tankto said storage tank for mixing with said waste to neutralize the same.